Molecular sieve compositions, catalysts thereof, their making and use in conversion processes

ABSTRACT

The invention relates to a conversion process of a feedstock, preferably an oxygenated feedstock, into one or more olefin(s), preferably ethylene and/or propylene, in the presence of a molecular sieve catalyst composition that includes a molecular sieve and a Group 3 metal oxide and/or an oxide of a Lanthanide or Actinide series element. The invention is also directed to methods of making and formulating the molecular sieve catalyst composition useful in a conversion process of a feedstock into one or more olefin(s).

FIELD OF THE INVENTION

The present invention relates to a conversion process utilizing amolecular sieve composition or a molecular sieve catalyst composition toform olefin(s). The invention is also directed to a method of making themolecular sieve composition and the molecular sieve catalystcomposition.

BACKGROUND OF THE INVENTION

Olefins are traditionally produced from petroleum feedstock by catalyticor steam cracking processes. These cracking processes, especially steamcracking, produce light olefin(s) such as ethylene and/or propylene froma variety of hydrocarbon feedstock. Ethylene and propylene are importantcommodity petrochemicals useful in a variety of processes for makingplastics and other chemical compounds.

The petrochemical industry has known for some time that oxygenates,especially alcohols, are convertible into light olefin(s). There arenumerous technologies available for producing oxygenates includingfermentation or reaction of synthesis gas derived from natural gas,petroleum liquids, carbonaceous materials including coal, recycledplastics, municipal waste or any other organic material. Generally, theproduction of synthesis gas involves a combustion reaction of naturalgas, mostly methane, and an oxygen source into hydrogen, carbon monoxideand/or carbon dioxide. Syngas production processes are well known, andinclude conventional steam reforming, autothermal reforming, or acombination thereof.

Methanol, the preferred alcohol for light olefin production, istypically synthesized from the catalytic reaction of hydrogen, carbonmonoxide and/or carbon dioxide in a methanol reactor in the presence ofa heterogeneous catalyst. For example, in one synthesis process methanolis produced using a copper/zinc oxide catalyst in a water-cooled tubularmethanol reactor. The preferred conversion process converts a feedstockcontaining methanol in the presence of a molecular sieve catalystcomposition to form one or more olefin(s), primarily ethylene and/orpropylene.

Molecular sieves are porous solids having pores of different sizes suchas zeolites or zeolite-type molecular sieves, carbons and oxides. Themost commercially useful molecular sieves for the petroleum andpetrochemical industries are known as zeolites, for examplealuminosilicate molecular sieves. Zeolites in general have a one-, two-or three-dimensional crystalline pore structure having uniformly sizedpores of molecular dimensions that selectively adsorb molecules that canenter the pores, and exclude those molecules that are too large.

There are many different types of molecular sieves well known to converta feedstock, especially an oxygenate containing feedstock, into one ormore olefin(s). For example, U.S. Pat. No. 5,367,100 describes the useof a well known zeolite, ZSM-5, to convert methanol into olefin(s); U.S.Pat. No. 4,062,905 discusses the conversion of methanol and otheroxygenates to ethylene and propylene using crystalline aluminosilicatezeolites, for example Zeolite T, ZK5, erionite and chabazite; U.S. Pat.No. 4,079,095 describes the use of ZSM-34 to convert methanol tohydrocarbon products such as ethylene and propylene; and U.S. Pat. No.4,310,440 describes producing light olefin(s) from an alcohol using acrystalline aluminophosphates, often represented by AlPO₄.

One of the most useful molecular sieves for converting methanol toolefin(s) is a silicoaluminophosphate molecular sieves.Silicoaluminophosphate (SAPO) molecular sieves contain athree-dimensional microporous crystalline framework structure of [SiO₂],[AlO₂] and [PO₂] corner sharing tetrahedral units. SAPO synthesis isdescribed in U.S. Pat. No. 4,440,871, which is herein fully incorporatedby reference. SAPO is generally synthesized by the hydrothermalcrystallization of a reaction mixture of silicon-, aluminum- andphosphorus-sources and at least one templating agent. Synthesis of aSAPO molecular sieve, its formulation into a SAPO catalyst, and its usein converting a hydrocarbon feedstock into olefin(s), particularly wherethe feedstock is methanol, is shown in U.S. Pat. Nos. 4,499,327,4,677,242, 4,677,243, 4,873,390, 5,095,163, 5,714,662 and 6,166,282, allof which are herein fully incorporated by reference.

Typically, molecular sieves are formed into molecular sieve catalystcompositions to improve their durability in commercial conversionprocesses. These molecular sieve catalyst compositions are formed bycombining a molecular sieve and a matrix material usually in thepresence of a binder. The purpose of the binder is hold the matrixmaterial, often a clay, to the molecular sieve. Binders and matrixmaterials are typically metal oxides that have a very small surface areasuch as less than ten square meters per gram (m²/g), more likely lessthan one m²/g of metal oxide. The use of binders and matrix materials inthe formation of molecular sieve catalyst compositions is well known.

U.S. Pat. No. 4,465,889 describes a catalyst composition of a silicalitemolecular sieve impregnated with a thorium, zirconium, or a titaniummetal oxide for use in converting methanol, dimethyl ether, or a mixturethereof into a hydrocarbon product rich in iso-C₄ compounds.

U.S. Pat. No. 6,180,828 discusses the use of a modified molecular sieveto produce methylamines from methanol and ammonia, where for example, asilicoaluminophosphate molecular sieve is combined with one of themodifiers, a zirconium oxide, a titanium oxide, a yttrium oxide,montmorillonite or kaolinite.

U.S. Pat. No. 5,417,949 relates to a process of converting noxiousnitrogen oxides in an oxygen containing effluent into nitrogen and waterusing a molecular sieve and a metal oxide binder, where the preferredbinder is titania and the molecular sieve is an aluminosilicatemolecular sieve.

Although the use of binders and matrix materials are known for use withmolecular sieves to form molecular sieve catalyst compositions, and thatthese catalyst compositions are useful in a process for convertingoxygenates into olefin(s), these binders and matrix materials typicallyonly serve to provide desired physical characteristics to the catalystcomposition, and have little to no effect on conversion and selectivityof the molecular sieve. It would therefore be desirable to have animproved molecular sieve catalyst composition having better conversionrates, olefin selectivity, longer lifetimes, and commercially desirableoperability and cost advantages.

SUMMARY OF THE INVENTION

This invention provides for a molecular sieve catalyst composition, amethod for making or formulating the molecular sieve catalystcomposition, and to their use in a conversion process for making one ormore olefin(s), particularly light olefin(s).

In one embodiment the invention is directed to a method for making themolecular sieve composition of the invention by combining, contacting,mixing, or the like, a molecular sieve and an active Group 3 metal oxideor an active oxide of the Lanthanide or Actinide series of elements. Thepreferred metal of the Group 3 metal oxide of the invention arelanthanum, yttrium and scandium. The most preferred active metal oxidesare scandium oxide, lanthanum oxide and yttrium oxide. More preferablythe molecular sieve is synthesized from the combination of two or moreof a silicon source, an aluminum source, and a phosphorous source,optionally in the presence of a templating agent.

In another embodiment the invention relates to a method for making amolecular sieve catalyst composition by combining, contacting, mixing,or the like, a matrix material, a binder, and at least one Group 3 metaloxide or at least one oxide of the Lanthanide or Actinide serieselements, wherein the active metal oxide is different from the binderand/or the matrix material. Preferably the Group 3 metal oxide is alanthanum metal oxide, a yttrium metal oxide or a scandium metal oxide,and the molecular sieve is synthesized from the combination of two ormore of a silicon source, an aluminum source, and a phosphorous source,optionally in the presence of a templating agent. In a more preferredembodiment, the molecular sieve, the binder and the matrix material aremade into a formulated molecular sieve catalyst composition that is thencontacted, mixed, combined, spray dried, or the like, with a Group 3metal oxide or an oxide of the Lanthanide or Actinide series elements.In an alternative embodiment, the Group 3 metal oxide or the oxide ofthe Lanthanide or Actinide series elements is included in the spraydrying of the formulated molecular sieve catalyst composition.

In yet another preferred method of the invention, a molecular sievecatalyst composition is made by a method comprising the steps of: (i)synthesizing a molecular sieve by the method comprising the steps of:(a) forming a first reaction mixture of at least one templating agentand at least two of the group consisting of a silicon source, aphosphorous source and an aluminum source; and (b) removing themolecular sieve from the first reaction mixture; (ii) forming a Group 3metal oxide and/or an oxide of the Lanthanide or Actinide serieselements by the method comprising the steps of: (a) forming a secondreaction mixture comprising a Group 3 metal oxide precursor and/or anoxide precursor of the Lanthanide or Actinide series elements and aprecipitating agent, (b) removing the Group 3 metal oxide and/or theoxide of the Lanthanide or Actinide series elements from the secondreaction mixture; and (iii) combining the molecular sieve and the activeGroup 3 metal oxide and/or the active oxide of the Lanthanide orActinide series elements.

In yet another embodiment, the invention is directed to a process forproducing olefin(s) in the presence of any of the above molecular sievecompositions and/or molecular sieve or formulated molecular sievecatalyst compositions. In particular, the process involves producingolefin(s) in a process for converting a feedstock, preferably afeedstock comprising an oxygenate, more preferably a feedstockcomprising an alcohol, and most preferably a feedstock comprisingmethanol, in the presence of one or more of the molecular sievecompositions, or catalyst compositions discussed above.

The invention is also directed to a composition of matter of any one ofthe molecular sieve compositions and/or molecular sieve catalystcompositions described above. The invention is further directed to theuse of a Group 3 metal oxide and/or an oxide of the Lanthanide orActinide series elements in combination with a formulated molecularsieve catalyst composition comprising a matrix material and/or a binder,a molecular sieve, and where the Group 3 metal oxide and/or the oxide ofthe Lanthanide or Actinide series elements is different from the matrixmaterial and/or the binder, for use in converting an oxygenatedfeedstock into one or more olefin(s).

DETAILED DESCRIPTION OF THE INVENTION

Introduction

The invention is directed toward a molecular sieve composition, to acatalyst composition thereof, and to their use in the conversion ofhydrocarbon feedstocks, particularly oxygenated feedstocks, intoolefin(s). It has been found that combining a molecular sieve with aGroup 3 metal oxide and/or an oxide of the Lanthanide or Actinide serieselements results in a molecular sieve composition or molecular sievecatalyst composition capable of converting more hydrocarbons, preferablyoxygenates, more particularly methanol, preferably into one or moreolefin(s) per gram of composition. The preferred metal oxides are thosehaving a Group 3 metal (for example yttrium, scandium and lanthanum) andthe Lanthanide or Actinide series elements (for example, cerium,neodymium, praseodymium and thorium) from the Periodic Table of Elementsusing the IUPAC format described in the CRC Handbook of Chemistry andPhysics, 78th Edition, CRC Press, Boca Raton, Fla. (1997). Also,surprisingly, the molecular sieve compositions and catalyst compositionsthereof have longer lifetimes because they are less susceptible to cokeformation, which is well known to reduce conversion of hydrocarbons,preferably oxygenates, into olefin(s). It has also been discovered thatthe molecular sieve compositions and catalyst compositions thereof aremore selective to olefin(s) such as propylene. In this regard, inparticular in the conversion of an oxygenate to at least ethylene andpropylene, the amount of unwanted ethane and propane made is reducedalong with other problematic compounds such as aldehydes and ketones,specifically acetaldehyde. Lastly, without being bound to any particulartheory, it is believed that because the molecular sieve composition andcatalyst compositions thereof are of a higher density, they tend not toexit a typical conversion process reactor via the exiting effluentstream or from the top of a regenerator often utilized to remove cokefrom a catalyst composition. The higher density compositions arebelieved to improve operability in the overall process and lower, forexample, catalyst composition losses thereby lowering overall conversioncosts.

Molecular Sieves

Molecular sieves have various chemical, physical, and frameworkcharacteristics. Molecular sieves have been well classified by theStructure Commission of the International Zeolite Association accordingto the rules of the IUPAC Commission on Zeolite Nomenclature. Aframework-type describes the topology and connectivity of thetetrahedrally coordinated atoms constituting the framework, and makes anabstraction of the specific properties for those materials.Framework-type zeolite and zeolite-type molecular sieves for which astructure has been established, are assigned a three letter code and aredescribed in the Atlas of Zeolite Framework Types, 5th edition,Elsevier, London, England (2001), which is herein fully incorporated byreference.

Non-limiting examples of these molecular sieves are the small poremolecular sieves, AEI, AFT, APC, ATN, ATT, ATV, AWW, BIK, CAS, CHA, CHI,DAC, DDR, EDI, ERI, GOO, KFI, LEV, LOV, LTA, MON, PAU, PHI, RHO, ROG,THO, and substituted forms thereof; the medium pore molecular sieves,AFO, AEL, EUO, HEU, FER, MEL, MFI, MTW, MTT, TON, and substituted formsthereof; and the large pore molecular sieves, EMT, FAU, and substitutedforms thereof. Other molecular sieves include ANA, BEA, CFI, CLO, DON,GIS, LTL, MER, MOR, MWW and SOD. Non-limiting examples of the preferredmolecular sieves, particularly for converting an oxygenate containingfeedstock into olefin(s), include AEL, AFY, BEA, CHA, EDI, FAU, FER,GIS, LTA, LTL, MER, MFI, MOR, MTT, MWW, TAM and TON. In one preferredembodiment, the molecular sieve of the invention has an AEI topology ora CHA topology, or a combination thereof, most preferably a CHAtopology.

Crystalline molecular sieve materials all have 3-dimensional,four-connected framework structure of corner-sharing TO₄ tetrahedra,where T is any tetrahedrally coordinated cation. These molecular sievesare typically described in terms of the size of the ring that defines apore, where the size is based on the number of T atoms in the ring.Other framework-type characteristics include the arrangement of ringsthat form a cage, and when present, the dimension of channels, and thespaces between the cages. See van Bekkum, et al., Introduction toZeolite Science and Practice, Second Completely Revised and ExpandedEdition, Volume 137, pages 1-67, Elsevier Science, B.V., Amsterdam,Netherlands (2001).

The small, medium and large pore molecular sieves have from a 4-ring toa 12-ring or greater framework-type. In a preferred embodiment, thezeolitic molecular sieves have 8-, 10- or 12-ring structures or largerand an average pore size in the range of from about 3 Å to 15 Å. In themost preferred embodiment, the molecular sieves, preferablysilicoaluminophosphate molecular sieves, have 8-rings and an averagepore size less than about 5 Å, preferably in the range of from 3 Å toabout 5 Å, more preferably from 3 Å to about 4.5 Å, and most preferablyfrom 3.5 Å to about 4.2 Å.

Molecular sieves have a molecular framework of one, preferably two ormore corner-sharing [TO₄] tetrahedral units, more preferably, two ormore [SiO₄], [AlO₄] and/or [PO₄] tetrahedral units, and most preferably[SiO₄], [AlO₄] and [PO₄] tetrahedral units. These silicon, aluminum, andphosphorous based molecular sieves and metal containing silicon,aluminum and phosphorous based molecular sieves have been described indetail in numerous publications including for example, U.S. Pat. No.4,567,029 (MeAPO where Me is Mg, Mn, Zn, or Co), U.S. Pat. No. 4,440,871(SAPO), European Patent Application EP-A-0 159 624 (ELAPSO where El isAs, Be, B, Cr, Co, Ga, Ge, Fe, Li, Mg, Mn, Ti or Zn), U.S. Pat. No.4,554,143 (FeAPO), U.S. Pat. Nos. 4,822,478, 4,683,217, 4,744,885(FeAPSO), EP-A-0 158 975 and U.S. Pat. No. 4,935,216 (ZnAPSO, EP-A-0 161489 (CoAPSO), EP-A-0 158 976 (ELAPO, where EL is Co, Fe, Mg, Mn, Ti orZn), U.S. Pat. No. 4,310,440 (AlPO₄), EP-A-0 158 350 (SENAPSO), U.S.Pat. No. 4,973,460 (LiAPSO), U.S. Pat. No. 4,789,535 (LiAPO), U.S. Pat.No. 4,992,250 (GeAPSO), U.S. Pat. No. 4,888,167 (GeAPO), U.S. Pat. No.5,057,295 (BAPSO), U.S. Pat. No. 4,738,837 (CrAPSO), U.S. Pat. Nos.4,759,919, and 4,851,106 (CrAPO), U.S. Pat. Nos. 4,758,419, 4,882,038,5,434,326 and 5,478,787 (MgAPSO), U.S. Pat. No. 4,554,143 (FeAPO), U.S.Pat. No. 4,894,213 (AsAPSO), U.S. Pat. No. 4,913,888 (AsAPO), U.S. Pat.Nos. 4,686,092, 4,846,956 and 4,793,833 (MnAPSO), U.S. Pat. Nos.5,345,011 and 6,156,931 (MnAPO), U.S. Pat. No. 4,737,353 (BeAPSO), U.S.Pat. No. 4,940,570 (BeAPO), U.S. Pat. Nos. 4,801,309, 4,684,617 and4,880,520 (TiAPSO), U.S. Pat. Nos. 4,500,651, 4,551,236 and 4,605,492(TiAPO), U.S. Pat. Nos. 4,824,554, 4,744,970 (CoAPSO), U.S. Pat. No.4,735,806 (GaAPSO) EP-A-0 293 937 (QAPSO, where Q is framework oxideunit [QO₂]), as well as U.S. Pat. Nos. 4,567,029, 4,686,093, 4,781,814,4,793,984, 4,801,364, 4,853,197, 4,917,876, 4,952,384, 4,956,164,4,956,165, 4,973,785, 5,241,093, 5,493,066 and 5,675,050, all of whichare herein fully incorporated by reference.

Other molecular sieves include those described in R. Szostak, Handbookof Molecular Sieves, Van Nostrand Reinhold, New York, N.Y. (1992), whichis herein fully incorporated by reference.

The more preferred silicon, aluminum and/or phosphorous containingmolecular sieves, and aluminum, phosphorous, and optionally silicon,containing molecular sieves include aluminophosphate (AlPO) molecularsieves and silicoaluminophosphate (SAPO) molecular sieves andsubstituted, preferably metal substituted, AlPO and SAPO molecularsieves. The most preferred molecular sieves are SAPO molecular sieves,and metal substituted SAPO molecular sieves.

In one embodiment, the molecular sieve, as described in many of the U.S.patents mentioned above, is represented by the empirical formula, on ananhydrous basis:mR:(M_(x)Al_(y)P_(z))O₂wherein R represents at least one templating agent, preferably anorganic templating agent; m is the number of moles of R per mole of(M_(x)Al_(y)P_(z))O₂ and m has a value from 0 to 1, preferably 0 to 0.5,and most preferably from 0 to 0.3; x, y, and z represent the molefraction of Al, P and M as tetrahedral oxides, where M is a metalselected from one of Group IA, IIA, IB, IIIB, IVB, VB, VIIB, VIIB, VIIIBand Lanthanide's of the Periodic Table of Elements, preferably M isselected from one of the group consisting of Co, Cr, Cu, Fe, Ga, Ge, Mg,Mn, Ni, Sn, Ti, Zn and Zr. In an embodiment, m is greater than or equalto 0.2, and x, y and z are greater than or equal to 0.01. In anotherembodiment, m is greater than 0.1 to about 1, x is greater than 0 toabout 0.25, y is in the range of from 0.4 to 0.5, and z is in the rangeof from 0.25 to 0.5, more preferably m is from 0.15 to 0.7, x is from0.01 to 0.2, y is from 0.4 to 0.5, and z is from 0.3 to 0.5.

Non-limiting examples of SAPO and AlPO molecular sieves of the inventioninclude one or a combination of SAPO-5, SAPO-8, SAPO-11, SAPO-16,SAPO-17, SAPO-18, SAPO-20, SAPO-31, SAPO-34, SAPO-35, SAPO-36, SAPO-37,SAPO-40, SAPO-41, SAPO-42, SAPO-44 (U.S. Pat. No. 6,162,415), SAPO-47,SAPO-56, AlPO-5, AlPO-11, AlPO-18, AlPO-31, AlPO-34, AlPO-36, AlPO-37,AlPO-46, and metal containing molecular sieves thereof. The morepreferred zeolite-type molecular sieves include one or a combination ofSAPO-18, SAPO-34, SAPO-35, SAPO-44, SAPO-56, AlPO-18 and AlPO-34, evenmore preferably one or a combination of SAPO-18, SAPO-34, AlPO-34 andAlPO-18, and metal containing molecular sieves thereof, and mostpreferably one or a combination of SAPO-34 and AlPO-18, and metalcontaining molecular sieves thereof.

In an embodiment, the molecular sieve is an intergrowth material havingtwo or more distinct phases of crystalline structures within onemolecular sieve composition. In particular, intergrowth molecular sievesare described in the U.S. patent application Ser. No. 09/924,016 filedAug. 7, 2001 and PCT WO 98/15496 published Apr. 16, 1998, both of whichare herein fully incorporated by reference. For example, SAPO-18,AlPO-18 and RUW-18 have an AEI framework-type, and SAPO-34 has a CHAframework-type. In another embodiment, the molecular sieve comprises atleast one intergrown phase of AEI and CHA framework-types, preferablythe molecular sieve has a greater amount of CHA framework-type to AEIframework-type, and more preferably the ratio of CHA to AEI is greaterthan 1:1 as determined by the DIFFaX method disclosed in U.S. patentapplication Ser. No. 09/924,106 filed Aug. 7, 2001, which is fullyincorporated herein by reference.

Molecular Sieve Synthesis

The synthesis of molecular sieves is described in many of the referencesdiscussed above. Generally, molecular sieves are synthesized by thehydrothermal crystallization of one or more of a source of aluminum, asource of phosphorous, a source of silicon, a templating agent, and ametal containing compound. Typically, a combination of sources ofsilicon, aluminum and phosphorous, optionally with one or moretemplating agents and/or one or more metal containing compounds areplaced in a sealed pressure vessel, optionally lined with an inertplastic such as polytetrafluoroethylene, and heated, under acrystallization pressure and temperature, until a crystalline materialis formed, and then recovered by filtration, centrifugation and/ordecanting.

In a preferred embodiment the molecular sieves are synthesized byforming a reaction product of a source of silicon, a source of aluminum,a source of phosphorous, one or more organic templating agent,preferably nitrogen containing organic templating agent(s), and one ormore active metal oxides. This particularly preferred embodiment resultsin the synthesis of a SAPO crystalline material that is then isolated byfiltration, centrifugation and/or decanting.

Non-limiting examples of silicon sources include a silicates, fumedsilica, for example, Aerosil-200 available from Degussa Inc., New York,N.Y., and CAB-O-SIL M-5, silicon compounds such as tetraalkylorthosilicates, for example, tetramethyl orthosilicate (TMOS) andtetraethylorthosilicate (TEOS), colloidal silicas or aqueous suspensionsthereof, for example Ludox-HS-40 sol available from E. I. du Pont deNemours, Wilmington, Del., silicic acid, alkali-metal silicate, or anycombination thereof. The preferred source of silicon is a silica sol.

Non-limiting examples of aluminum sources include aluminum-containingcompositions such as aluminum alkoxides, for example aluminumisopropoxide, aluminum phosphate, aluminum hydroxide, sodium aluminate,pseudo-boehmite, gibbsite and aluminum trichloride, or any combinationsthereof. A preferred source of aluminum is pseudo-boehmite, particularlywhen producing a silicoaluminophosphate molecular sieve.

Non-limiting examples of phosphorous sources, which may also includealuminum-containing phosphorous compositions, includephosphorous-containing, inorganic or organic, compositions such asphosphoric acid, organic phosphates such as triethyl phosphate, andcrystalline or amorphous aluminophosphates such as AlPO₄, phosphoroussalts, or combinations thereof. The preferred source of phosphorous isphosphoric acid, particularly when producing a silicoaluminophosphate.

Templating agents are generally compounds that contain elements of Group15 of the Periodic Table of Elements, particularly nitrogen, phosphorus,arsenic and antimony, more preferably nitrogen or phosphorous, and mostpreferably nitrogen. Typical templating agents of Group 15 of thePeriodic Table of elements also contain at least one alkyl or arylgroup, preferably an alkyl or aryl group having from 1 to 10 carbonatoms, and more preferably from 1 to 8 carbon atoms. The preferredtemplating agents are nitrogen-containing compounds such as amines andquaternary ammonium compounds.

The quaternary ammonium compounds, in one embodiment, are represented bythe general formula R₄N⁺, where each R is hydrogen or a hydrocarbyl orsubstituted hydrocarbyl group, preferably an alkyl group or an arylgroup having from 1 to 10 carbon atoms. In one embodiment, thetemplating agents include a combination of one or more quaternaryammonium compound(s) and one or more of a mono-, di- or tri-amine.

Non-limiting examples of templating agents include tetraalkyl ammoniumcompounds including salts thereof such as tetramethyl ammonium compoundsincluding salts thereof, tetraethyl ammonium compounds including saltsthereof, tetrapropyl ammonium compounds including salts thereof, andtetrabutylammonium compounds including salts thereof, cyclohexylamine,morpholine, di-n-propylamine (DPA), tripropylamine, triethylamine (TEA),triethanolamine, piperidine, cyclohexylamine, 2-methylpyridine,N,N-dimethylbenzylamine, N,N-diethylethanolamine, dicyclohexylamine,N,N-dimethylethanolamine, choline, N,N′-dimethylpiperazine,1,4-diazabicyclo(2,2,2)octane, N′,N′,N,N-tetramethyl-(1,6)hexanediamine,N-methyldiethanolamine, N-methyl-ethanolamine, N-methyl piperidine,3-methyl-piperidine, N-methylcyclohexylamine, 3-methylpyridine,4-methyl-pyridine, quinuclidine, N,N′-dimethyl-1,4-diazabicyclo(2,2,2)octane ion; di-n-butylamine, neopentylamine, di-n-pentylamine,isopropylamine, t-butyl-amine, ethylenediamine, pyrrolidine, and2-imidazolidone.

The preferred templating agent or template is a tetraethylammoniumcompound, such as tetraethyl ammonium hydroxide (TEAOH), tetraethylammonium phosphate, tetraethyl ammonium fluoride, tetraethyl ammoniumbromide, tetraethyl ammonium chloride and tetraethyl ammonium acetate.The most preferred templating agent is TEAOH and salts thereof,particularly when producing a silicoaluminophosphate molecular sieve. Inone embodiment, a combination of two or more of any of the abovetemplating agents is used in combination with two or more of a silicon-,aluminum-, and phosphorous-source.

Generally, the synthesis mixture described above is sealed in a vesseland heated, preferably under autogenous pressure, to a temperature inthe range of from about 80° C. to about 250° C., preferably from about100° C. to about 250° C., more preferably from about 125° C. to about225° C., even more preferably from about 150° C. to about 180° C.

In yet another embodiment, the crystallization temperature is increasedgradually or stepwise during synthesis, preferably the crystallizationtemperature is maintained constant, for a period of time effective toform a crystalline product. The time required to form the crystallineproduct is typically from immediately up to several weeks, the durationof which is usually dependent on the temperature; the higher thetemperature the shorter the duration. In one embodiment, the crystallineproduct is formed under heating from about 30 minutes to around 2 weeks,preferably from about 45 minutes to about 240 hours, and more preferablyfrom about 1 hour to about 120 hours.

In one embodiment, the synthesis of a molecular sieve is aided by seedsfrom another or the same framework type molecular sieve.

The hydrothermal crystallization is carried out with or withoutagitation or stirring, for example stirring or tumbling. The stirring oragitation during the crystallization period may be continuous orintermittent, preferably continuous agitation. Typically, thecrystalline molecular sieve product is formed, usually in a slurrystate, and is recovered by any standard technique well known in the art,for example centrifugation or filtration. The isolated or separatedcrystalline product, in an embodiment, is washed, typically, using aliquid such as water, from one to many times. The washed crystallineproduct is then optionally dried, preferably in air.

One method for crystallization involves subjecting an aqueous reactionmixture containing an excess amount of a templating agent, subjectingthe mixture to crystallization under hydrothermal conditions,establishing an equilibrium between molecular sieve formation anddissolution, and then, removing some of the excess templating agentand/or organic base to inhibit dissolution of the molecular sieve. Seefor example U.S. Pat. No. 5,296,208, which is herein fully incorporatedby reference.

Other methods for synthesizing molecular sieves or modifying molecularsieves are described in U.S. Pat. No. 5,879,655 (controlling the ratioof the templating agent to phosphorous), U.S. Pat. No. 6,005,155 (use ofa modifier without a salt), U.S. Pat. No. 5,475,182 (acid extraction),U.S. Pat. No. 5,962,762 (treatment with transition metal), U.S. Pat.Nos. 5,925,586 and 6,153,552 (phosphorous modified), U.S. Pat. No.5,925,800 (monolith supported), U.S. Pat. No. 5,932,512 (fluorinetreated), U.S. Pat. No. 6,046,373 (electromagnetic wave treated ormodified), U.S. Pat. No. 6,051,746 (polynuclear aromatic modifier), U.S.Pat. No. 6,225,254 (heating template), PCT WO 01/36329 published May 25,2001 (surfactant synthesis), PCT WO 01/25151 published Apr. 12, 2001(staged acid addition), PCT WO 01/60746 published Aug. 23, 2001 (siliconoil), U.S. patent application Ser. No. 09/929,949 filed Aug. 15, 2001(cooling molecular sieve), U.S. patent application Ser. No. 09/615,526filed Jul. 13, 2000 (metal impregnation including copper), U.S. patentapplication Ser. No. 09/672,469 filed Sep. 28, 2000 (conductivemicrofilter), and U.S. patent application Ser. No. 09/754,812 filed Jan.4, 2001(freeze drying the molecular sieve), which are all herein fullyincorporated by reference.

In one preferred embodiment, when a templating agent is used in thesynthesis of a molecular sieve, it is preferred that the templatingagent is substantially, preferably completely, removed aftercrystallization by numerous well known techniques, for example, heattreatments such as calcination. Calcination involves contacting themolecular sieve containing the templating agent with a gas, preferablycontaining oxygen, at any desired concentration at an elevatedtemperature sufficient to either partially or completely decompose andoxidize the templating agent.

Molecular sieve have either a high silicon (Si) to aluminum (Al) ratioor a low silicon to aluminum ratio, however, a low Si/Al ratio ispreferred for SAPO synthesis. In one embodiment, the molecular sieve hasa Si/Al ratio less than 0.65, preferably less than 0.40, more preferablyless than 0.32, and most preferably less than 0.20. In anotherembodiment the molecular sieve has a Si/Al ratio in the range of fromabout 0.65 to about 0.10, preferably from about 0.40 to about 0.10, morepreferably from about 0.32 to about 0.10, and more preferably from about0.32 to about 0.15.

The pH of a reaction mixture containing at a minimum a silicon-,aluminum-, and/or phosphorous-composition, and a templating agent,should be in the range of from 2 to 10, preferably in the range of from4 to 9, and most preferably in the range of from 5 to 8.

Group 3 Metal Oxides and Oxides of the Lanthanide or Actinide Series

The Group 3 metal oxides and oxides of the Lanthanide or Actinide seriesof the invention are those metal oxides, different from typical bindersand/or matrix materials, that, when used in combination with a molecularsieve, provide benefits in catalytic conversion processes. Preferredactive metal oxides are those metal oxides having a Group 3 metal, suchas scandium, yttrium and lanthanum, or a metal from the Lanthanide orActinide series, such as cerium, praseodymium, neodymium, samarium,europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium,ytterbium, lutetium and thorium. The most preferred active metal oxidesare scandium oxide, lanthanum oxide, yttrium oxide, cerium oxide,praseodymium oxide, neodymium oxide or mixtures thereof.

While there are many different benefits in catalytic conversionprocesses, one of the most desirable is an extension of the catalystcomposition life. Quantification of the extension in the catalystcomposition life is determined by the Lifetime Enhancement Index (LEI)as defined by the following equation:${{{LEI} =}\quad}{\quad\frac{\text{Lifetime~~of~~Catalyst~~in~~Combination with~~Active~~Metal~~Oxide(s)~~}}{{Lifetime}\quad{of}\quad{Catalyst}}\quad}$where the lifetime of the catalyst or catalyst composition, is measuredin the same process under the same conditions, and is the cumulativeamount of feedstock processed per gram of catalyst composition until theconversion of feedstock by the catalyst composition falls below somedefined level, for example 10%. A mixture containing an inactive metaloxide will have little to no effect on the lifetime of the catalystcomposition, or will shorten the lifetime of the catalyst composition,and will therefore have a LEI less than or equal to 1. Active metaloxides of the invention are those Group 3 metal oxides, including oxidesof the Lanthanide and Actinide series that when used in combination witha molecular sieve, provide a molecular sieve catalyst composition thathas a LEI greater than 1. By definition, a molecular sieve catalystcomposition that has not been combined with an active metal oxide willhave a LEI equal to 1.0.

In one embodiment, the active Group 3 metal oxide and/or the activeoxides of the Lanthanide and Actinide series when combined with amolecular sieve enhances the lifetime of the molecular sieve in aconversion process of a feedstock comprising methanol, preferably intoone or more olefin(s). In another embodiment, the molecular sievecomposition, molecular sieve catalyst composition, and formulatedmolecular sieve catalyst composition of the invention, each containingan active metal oxide, will have a LEI greater than 1. In a preferredembodiment, the LEI of the molecular sieve composition, molecular sievecatalyst composition, or formulated molecular sieve catalystcomposition, all containing one or more Group 3 metal oxides and/or oneor more active oxides of the Lanthanide and Actinide series is greaterthan 1.1, preferably greater than 1.3, more preferably greater than 1.5,even more preferably greater than 1.7 and most preferably greater than2. In an alternative embodiment, the LEI of the molecular sievecomposition, molecular sieve catalyst composition, or formulatedmolecular sieve catalyst composition, all containing at least one activeGroup 3 metal oxide and/or at least one active oxide of the Lanthanideand Actinide series is in the range of from greater than 1 to 30, morepreferably in the range of from about 1.2 to 25, and most preferably inthe range of from about 1.5 to about 20.

In one embodiment, the active Group 3 metal oxides of the invention,including oxides of the Lanthanide and Actinide series elements, arenon-acidic or basic metal oxides.

In another embodiment, when combining more than one metal oxide of theinvention with a molecular sieve, the metal oxides are each madeseparately and then contacted together, or pre-combined, with themolecular sieve, or alternatively, each metal oxide is contactedsequentially with the molecular sieve. In an embodiment, the metaloxides of the invention are mixed together in a slurry or hydrated stateor in a substantially dry or dried state, preferably the metal oxidesare contacted in a hydrated state.

The metal oxides of the invention are prepared using a variety ofmethods. It is preferable that the metal oxide is made from metal oxideprecursors, such as metal salts. Other suitable sources of the metaloxides include compounds that form these metal oxides duringcalcination, such as oxychlorides and nitrates. Alkoxides are alsosources of the metal oxides of the invention, for example yttriumn-propoxide.

In one embodiment, a preferred Group 3 metal oxide or oxide of theLanthanide or Actinide series is hydrothermally treated under conditionsthat include a temperature of at least 80° C., preferably at least 100°C. The hydrothermal treatment typically takes place in a sealed vesselat greater than atmospheric pressure. However, a preferred mode oftreatment involves the use of an open vessel under reflux conditions.Agitation of the Group 3 metal oxide or the oxide of the Lanthanide orActinide series in the liquid medium, for example, by the action ofrefluxing liquid and/or stirring, promotes the effective interaction ofthe oxide with the liquid medium. The duration of the contact of theoxide with the liquid medium is preferably at least 1 hour, preferablyat least 8 hours. The liquid medium for this treatment preferably has apH of about 7 or greater, preferably 9 or greater. Non-limiting examplesof suitable liquid media include water, hydroxide solutions (includinghydroxides of NH₄ ⁺, Na⁺, K⁺, Mg²⁺, and Ca²⁺), carbonate and bicarbonatesolutions (including carbonates and bicarbonates of NH₄ ⁺, Na⁺, K⁺,Mg²⁺, and Ca²⁺), pyridine and its derivatives, and alkyl/hydroxylamines.

In yet another embodiment, the active Group 3 metal oxide or the activeoxide of the Lanthanide or Actinide series is prepared, for example, byfirst preparing a liquid solution comprising a source of a Group 3 metalor combination of Group 3 metals or one or more elements of theLanthanide or Actinide series of elements. Suitable sources for theGroup 3 metal or the Lanthanide or Actinide series element include, butare not limited to, salts containing a Group 3 metal or Lanthanide orActinide element, such as nitrates, sulfates and halides.

This solution containing a source of a Group 3 metal or a source of aLanthanide or Actinide series element, or combinations thereof is thensubjected to conditions sufficient to cause precipitation of the solidmetal oxide, such as by the addition of a precipitating reagent to thesolution. For example, the precipitating agent(s) preferably is a basesuch as sodium hydroxide or ammonium hydroxide. Water is a preferredsolvent for these solutions. The temperature at which the liquidmedium(s) is maintained during the precipitation is preferably less thanabout 200° C., preferably in the range of from about 0° C. to about 200°C. This liquid medium(s) is preferably maintained at an ambienttemperature, for example room temperature or the liquid is cooled orheated. A particular range of temperatures for precipitation is fromabout 20° C. to about 100° C. The resulting gel is preferably thenhydrothermally treated at temperatures of at least 80° C., preferably atleast 100° C. The hydrothermal treatment typically takes place in asealed vessel at greater than atmospheric pressure. The gel, in oneembodiment, is hydrothermally treated for up to 10 days, preferably upto 5 days, most preferably up to 3 days. The resulting material is thenrecovered, for example by filtration or centrifugation, and washed anddried. The resulting material is preferably then calcined, preferably inan oxidizing atmosphere, at a temperature of at least 400° C.,preferably at least 500° C., and more preferably from about 600° C. toabout 900° C., and most preferably from about 600° C. to about 800° C.The calcination time is preferably up to 48 hours, preferably for about0.5 to 24 hours, and more preferably for about 1.0 to 10 hours.

Molecular Sieve Composition

The molecular sieve composition of the invention includes any one of themolecular sieves previously described and one or more of the Group 3metal oxides and/or one or more oxide(s) of a Lanthanide or Actinideseries element described above. Most preferably, the molecular sievesare those resulting from the synthesis mixture of phosphorous-,aluminum-, and/or silicon-containing components, preferably whilestirring and/or agitation and/or seeding with a crystalline material,optionally in the presence of an alkali metal, in a solvent such aswater, and one or more templating agents, to form a synthesis mixturethat is then heated under crystallization conditions of pressure andtemperature as described in U.S. Pat. Nos. 4,440,871, 4,861,743,5,096,684, and 5,126,308, which are all herein fully incorporated byreference.

In the more preferred embodiment, the molecular sieve is first formedand is then combined with an active Group 3 metal oxide or an activeoxide of a Lanthanide or Actinide series element, preferably in asubstantially dry, dried, or calcined state, most preferably themolecular sieve and active Group 3 metal oxide or active oxide of aLanthanide or Actinide series element are physically mixed in theircalcined state to form the preferred molecular sieve composition of theinvention. Without being bound by any particular theory, it is believedthat intimate mixing of the molecular sieve and the active Group 3 metaloxide or the active oxide of a Lanthanide or Actinide series elementimprove conversion processes using the molecular sieve composition andcatalyst composition of the invention. Intimate mixing may be achievedby any method known in the art, such as mixing with a mixer muller, drummixer, ribbon/paddle blender, kneader, or the like.

In one embodiment, the molecular sieve composition or molecular sievecatalyst composition has a weight ratio of the molecular sieve to theactive Group 3 metal oxide or the active oxide of a Lanthanide orActinide series element in the range of from 5 weight percent to 800weight percent, particularly in the range from 10 weight percent to 600weight percent, more particularly from 20 weight percent to 500 weightpercent, and most preferably from 30 weight percent to 400 weightpercent.

Method for Making Molecular Sieve Catalyst Compositions

Once the molecular sieve is synthesized or the molecular sievecomposition is made, depending on the requirements of the particularconversion process, the molecular sieve or the molecular sievecomposition is then formulated into a molecular sieve catalystcomposition, particularly for commercial use. A molecular sieve catalystcomposition is made or formulated by combining a molecular sievesynthesized above or a molecular sieve composition above, with a binderand/or a matrix material. In one embodiment, where the molecular sievesynthesized above is formulated into a molecular sieve catalystcomposition, the active Group 3 metal oxide or the active oxide of aLanthanide or Actinide series element is then combined with theformulated molecular sieve catalyst composition. It is also anembodiment of the invention that a first formulated molecular sievecatalyst is combined with an active Group 3 metal oxide or an activeoxide of a Lanthanide or Actinide series element that is then formulatedtogether into a second formulated molecular sieve catalyst composition.These formulated molecular sieve catalyst composition are then formedinto useful shape and sized particles by well-known techniques such asspray drying, pelletizing, extrusion, and the like.

There are many different binders that are useful in forming molecularsieve catalyst compositions or formulated molecular sieve catalystcompositions. In one preferred embodiment, the binder is different fromat least one of, most preferably any, of the Group 3 metal oxides or theoxides of a Lanthanide or Actinide series element discussed above.Non-limiting examples of binders that are useful alone or in combinationinclude various types of hydrated alumina, silicas, and/or otherinorganic oxide sol. One preferred alumina containing sol is aluminumchlorhydrol or chlorhydrate. The inorganic oxide sol acts like gluebinding the synthesized molecular sieves and other materials such as thematrix together, particularly after thermal treatment. Upon heating, theinorganic oxide sol, preferably having a low viscosity, is convertedinto an inorganic oxide matrix component. For example, an alumina solwill convert to an aluminum oxide matrix following heat treatment.

Aluminum chlorhydrate, a hydroxylated aluminum based sol containing achloride counter ion, has the general formula ofAl_(m)O_(n)(OH)_(o)Cl_(p).x(H₂O) wherein m is 1 to 20, n is 1 to 8, o is5 to 40, p is 2 to 15, and x is 0 to 30. In one embodiment, the binderis Al₁₃O₄(OH)₂₄Cl₇.12(H₂O) as is described in G. M. Wolterman, et al.,Stud. Surf. Sci. and Catal., 76, pages 105-144 (1993), which is hereinincorporated by reference. In another embodiment, one or more bindersare combined with one or more other non-limiting examples of aluminamaterials such as aluminum oxyhydroxide, γ-alumina, boehmite, diaspore,and transitional aluminas such as α-alumina, β-alumina, γ-alumina,δ-alumina, ε-alumina, κ-alumina, and ρ-alumina, aluminum trihydroxide,such as gibbsite, bayerite, nordstrandite, doyelite, and mixturesthereof.

In another embodiment, the binders are alumina sols, predominantlycomprising aluminum oxide, optionally including some silicon. In yetanother embodiment, the binders are peptized alumina made by treatingalumina hydrates such as pseudobohemite, with an acid, preferably anacid that does not contain a halogen, to prepare sols or aluminum ionsolutions. Non-limiting examples of commercially available colloidalalumina sols include Nalco 8676 available from Nalco Chemical Co.,Naperville, Ill., and Nyacol available from The PQ Corporation, ValleyForge, Pa.

Preferably, the molecular sieve compositions described above arecombined with one or more matrix material(s). In the preferredembodiment, the matrix material is different from the Group 3 metaloxide or the oxide of a Lanthanide or Actinide series element. Matrixmaterials are typically effective in reducing overall catalyst cost, actas thermal sinks assisting in shielding heat from the catalystcomposition for example during regeneration, densifying the catalystcomposition, and increasing catalyst strength such as crush strength andattrition resistance.

Non-limiting examples of matrix materials include one or more of:non-active metal oxides including magnesia, beryllia, quartz, silica orsols, and mixtures thereof, for example silica-magnesia,silica-zirconia, silica-titania, silica-alumina andsilica-alumina-thoria. In an embodiment, matrix materials are naturalclays such as those from the families of montmorillonite and kaolin.These natural clays include sabbentonites and those kaolins known as,for example, Dixie, McNamee, Georgia and Florida clays. Non-limitingexamples of other matrix materials include: haloysite, kaolinite,dickite, nacrite, or anauxite. In one embodiment, the matrix material,preferably any of the clays, are subjected to well known modificationprocesses such as calcination and/or acid treatment and/or chemicaltreatment.

In one preferred embodiment, the matrix material is a clay or aclay-type composition, preferably the clay or clay-type compositionhaving a low iron or titania content, and most preferably the matrixmaterial is kaolin. Kaolin has been found to form a pumpable, high solidcontent slurry, it has a low fresh surface area, and it packs togethereasily due to its platelet structure. A preferred average particle sizeof the matrix material, most preferably kaolin, is from about 0.1 μm toabout 0.6 μm with a D90 particle size distribution of less than about 1μm.

In one embodiment, the binder, the molecular sieve composition and thematrix material are combined in the presence of a liquid to form amolecular sieve catalyst composition, where the amount of binder is fromabout 2% by weight to about 30% by weight, preferably from about 5% byweight to about 20% by weight, and more preferably from about 7% byweight to about 15% by weight, based on the total weight of the binder,the molecular sieve and matrix material, excluding the liquid (aftercalcination).

In another embodiment, the weight ratio of the binder to the matrixmaterial used in the formation of the molecular sieve catalystcomposition is from 0:1 to 1:15, preferably 1:15 to 1:5, more preferably1:10 to 1:4, and most preferably 1:6 to 1:5. It has been found that ahigher sieve content, lower matrix content, increases the molecularsieve catalyst composition performance, however, lower sieve content,higher matrix material, improves the attrition resistance of thecomposition.

Upon combining the molecular sieve composition and the matrix material,optionally with a binder, in a liquid to form a slurry, mixing,preferably rigorous mixing is needed to produce a substantiallyhomogeneous mixture containing the molecular sieve composition.Non-limiting examples of suitable liquids include one or a combinationof water, alcohol, ketones, aldehydes, and/or esters. The most preferredliquid is water. In one embodiment, the slurry is colloid-milled for aperiod of time sufficient to produce the desired slurry texture,sub-particle size, and/or sub-particle size distribution.

The molecular sieve composition and matrix material, and the optionalbinder, are in the same or different liquid, and are combined in anyorder, together, simultaneously, sequentially, or a combination thereof.In the preferred embodiment, the same liquid, preferably water is used.The molecular sieve composition, matrix material, and optional binder,are combined in a liquid as solids, substantially dry or in a driedform, or as slurries, together or separately. If solids are addedtogether as dry or substantially dried solids, it is preferable to add alimited and/or controlled amount of liquid.

In one embodiment, the slurry of the molecular sieve composition, binderand matrix materials is mixed or milled to achieve a sufficientlyuniform slurry of sub-particles of the molecular sieve catalystcomposition that is then fed to a forming unit that produces themolecular sieve catalyst composition. In a preferred embodiment, theforming unit is spray dryer. Typically, the forming unit is maintainedat a temperature sufficient to remove most of the liquid from theslurry, and from the resulting molecular sieve catalyst composition. Theresulting catalyst composition when formed in this way takes the form ofmicrospheres.

When a spray drier is used as the forming unit, typically, the slurry ofthe molecular sieve composition and matrix material, and optionally abinder, is co-fed to the spray drying volume with a drying gas with anaverage inlet temperature ranging from 200° C. to 550° C., and acombined outlet temperature ranging from 100° C. to about 225° C. In anembodiment, the average diameter of the spray dried formed catalystcomposition is from about 40 μm to about 300 μm, preferably from about50 μm to about 250 μm, more preferably from about 50 μm to about 200 μm,and most preferably from about 65 μm to about 90 μm.

Other methods for forming a molecular sieve catalyst composition isdescribed in U.S. patent application Ser. No. 09/617,714 filed Jul. 17,2000 (spray drying using a recycled molecular sieve catalystcomposition), which is herein incorporated by reference.

In another embodiment, the molecular sieve catalyst composition orformulated molecular sieve catalyst composition contains from about 1%to about 80%, more preferably from about 5% to about 60%, and mostpreferably from about 5% to about 50%, by weight of the molecular sievebased on the total weight of the molecular sieve catalyst composition orformulated molecular sieve catalyst composition.

In another embodiment, the weight percent of binder in or on the spraydried molecular sieve catalyst composition based on the total weight ofthe binder, molecular sieve composition, matrix material and activeGroup 3 metal oxide(s) is from about 2% by weight to about 30% byweight, preferably from about 5% by weight to about 20% by weight, andmore preferably from about 7% by weight to about 15% by weight.

Once the molecular sieve catalyst composition is formed in asubstantially dry or dried state, to further harden and/or activate theformed catalyst composition, a heat treatment such as calcination, at anelevated temperature is usually performed. A conventional calcinationenvironment is air that typically includes a small amount of watervapor. Typical calcination temperatures are in the range from about 400°C. to about 1,000° C., preferably from about 500° C. to about 800° C.,and most preferably from about 550° C. to about 700° C., preferably in acalcination environment such as air, nitrogen, helium, flue gas(combustion product lean in oxygen), or any combination thereof.

In a preferred embodiment, the molecular sieve catalyst composition isheated in nitrogen at a temperature of from about 600° C. to about 700°C. Heating is carried out for a period of time typically from 30 minutesto 15 hours, preferably from 1 hour to about 10 hours, more preferablyfrom about 1 hour to about 5 hours, and most preferably from about 2hours to about 4 hours.

In one embodiment, the molecular sieve catalyst composition orformulated molecular sieve catalyst composition of the invention has adensity in the range of from 0.5 g/cc to 5 g/cc, preferably from in therange of from 0.6 g/cc to 5 g/cc, more preferably in the range of from0.7 g/cc to 4 g/cc, and most preferably in the range of from 0.8 g/cc to3 g/cc.

Process for Using the Molecular Sieve Catalyst Compositions

The molecular sieve compositions and catalyst compositions describedabove are useful in a variety of processes including: cracking, of forexample a naphtha feed to light olefin(s) (U.S. Pat. No. 6,300,537) orhigher molecular weight (MW) hydrocarbons to lower MW hydrocarbons;hydrocracking, of for example heavy petroleum and/or cyclic feedstock;isomerization, of for example aromatics such as xylene, polymerization,of for example one or more olefin(s) to produce a polymer product;reforming; hydrogenation; dehydrogenation; dewaxing, of for examplehydrocarbons to remove straight chain paraffins; absorption, of forexample alkyl aromatic compounds for separating out isomers thereof;alkylation, of for example aromatic hydrocarbons such as benzene andalkyl benzene, optionally with propylene to produce cumeme or with longchain olefins; transalkylation, of for example a combination of aromaticand polyalkylaromatic hydrocarbons; dealkylation; hydrodecylization;disproportionation, of for example toluene to make benzene andparaxylene; oligomerization, of for example straight and branched chainolefin(s); and dehydrocyclization.

Preferred processes are conversion processes including: naphtha tohighly aromatic mixtures; light olefin(s) to gasoline, distillates andlubricants; oxygenates to olefin(s); light paraffins to olefins and/oraromatics; and unsaturated hydrocarbons (ethylene and/or acetylene) toaldehydes for conversion into alcohols, acids and esters. The mostpreferred process of the invention is a process directed to theconversion of a feedstock comprising one or more oxygenates to one ormore olefin(s).

The molecular sieve compositions and molecular sieve catalystcompositions and formulated versions thereof described above areparticularly useful in conversion processes of different feedstock.Typically, the feedstock contains one or more aliphatic-containingcompounds that include alcohols, amines, carbonyl compounds for examplealdehydes, ketones and carboxylic acids, ethers, halides, mercaptans,sulfides, and the like, and mixtures thereof. The aliphatic moiety ofthe aliphatic-containing compounds typically contains from 1 to about 50carbon atoms, preferably from 1 to 20 carbon atoms, more preferably from1 to 10 carbon atoms, and most preferably from 1 to 4 carbon atoms.

Non-limiting examples of aliphatic-containing compounds include:alcohols such as methanol and ethanol, alkyl-mercaptans such as methylmercaptan and ethyl mercaptan, alkyl-sulfides such as methyl sulfide,alkyl-amines such as methyl amine, alkyl-ethers such as dimethyl ether,diethyl ether and methylethyl ether, alkyl-halides such as methylchloride and ethyl chloride, alkyl ketones such as dimethyl ketone,formaldehydes, and various acids such as acetic acid.

In a preferred embodiment of the process of the invention, the feedstockcontains one or more oxygenates, more specifically, one or more organiccompound(s) containing at least one oxygen atom. In the most preferredembodiment of the process of invention, the oxygenate in the feedstockis one or more alcohol(s), preferably aliphatic alcohol(s) where thealiphatic moiety of the alcohol(s) has from 1 to 20 carbon atoms,preferably from 1 to 10 carbon atoms, and most preferably from 1 to 4carbon atoms. The alcohols useful as feedstock in the process of theinvention include lower straight and branched chain aliphatic alcoholsand their unsaturated counterparts.

Non-limiting examples of oxygenates include methanol, ethanol,n-propanol, isopropanol, methyl ethyl ether, dimethyl ether, diethylether, di-isopropyl ether, formaldehyde, dimethyl carbonate, dimethylketone, acetic acid, and mixtures thereof.

In the most preferred embodiment, the feedstock is selected from one ormore of methanol, ethanol, dimethyl ether, diethyl ether or acombination thereof, more preferably methanol and dimethyl ether, andmost preferably methanol.

The various feedstocks discussed above, particularly a feedstockcontaining an oxygenate, more particularly a feedstock containing analcohol, is converted primarily into one or more olefin(s). Theolefin(s) or olefin monomer(s) produced from the feedstock typicallyhave from 2 to 30 carbon atoms, preferably 2 to 8 carbon atoms, morepreferably 2 to 6 carbon atoms, still more preferably 2 to 4 carbonsatoms, and most preferably ethylene and/or propylene.

Non-limiting examples of olefin monomer(s) include ethylene, propylene,butene-1, pentene-1,4-methyl-pentene-1, hexene-1, octene-1 and decene-1,preferably ethylene, propylene, butene-1, pentene-1,4-methyl-pentene-1,hexene-1, octene-1 and isomers thereof. Other olefin monomer(s) includeunsaturated monomers, diolefins having 4 to 18 carbon atoms, conjugatedor nonconjugated dienes, polyenes, vinyl monomers and cyclic olefins.

In the most preferred embodiment, the feedstock, preferably of one ormore oxygenates, is converted in the presence of a molecular sievecatalyst composition into olefin(s) having 2 to 6 carbons atoms,preferably 2 to 4 carbon atoms. Most preferably, the olefin(s), alone orcombination, are converted from a feedstock containing an oxygenate,preferably an alcohol, most preferably methanol, to the preferredolefin(s) ethylene and/or propylene.

The are many processes used to convert feedstock into olefin(s)including various cracking processes such as steam cracking, thermalregenerative cracking, fluidized bed cracking, fluid catalytic cracking,deep catalytic cracking, and visbreaking.

The most preferred process is generally referred to as gas-to-olefins(GTO) or alternatively, methanol-to-olefins (MTO). In a MTO process,typically an oxygenated feedstock, most preferably a methanol containingfeedstock, is converted in the presence of a molecular sieve compositionor catalyst composition thereof into one or more olefin(s), preferablyand predominantly, ethylene and/or propylene, often referred to as lightolefin(s).

In one embodiment of the process for conversion of a feedstock,preferably a feedstock containing one or more oxygenates, the amount ofolefin(s) produced based on the total weight of hydrocarbon produced isgreater than 50 weight percent, preferably greater than 60 weightpercent, more preferably greater than 70 weight percent, and mostpreferably greater than 75 weight percent. In another embodiment of theprocess for conversion of one or more oxygenates to one or moreolefin(s), the amount of ethylene and/or propylene produced based on thetotal weight of hydrocarbon product produced is greater than 65 weightpercent, preferably greater than 70 weight percent, more preferablygreater than 75 weight percent, and most preferably greater than 78weight percent.

In another embodiment of the process for conversion of one or moreoxygenates to one or more olefin(s), the amount ethylene produced inweight percent based on the total weight of hydrocarbon productproduced, is greater than 30 weight percent, more preferably greaterthan 35 weight percent, and most preferably greater than 40 weightpercent. In yet another embodiment of the process for conversion of oneor more oxygenates to one or more olefin(s), the amount of propyleneproduced in weight percent based on the total weight of hydrocarbonproduct produced is greater than 20 weight percent, preferably greaterthan 25 weight percent, more preferably greater than 30 weight percent,and most preferably greater than 35 weight percent.

In the most preferred embodiments, the molecular sieve catalystcomposition comprises a silicoaluminophosphate and an active Group 3metal oxide or oxide of the Lanthanide or Actinide series elements andthe oxygenates include methanol and/or dimethyl ether.

In another embodiment, in a process for conversion an oxygenatecomprising methanol and dimethylether to ethylene and propylene in thepresence of a molecular sieve and an active metal oxide, preferably amolecular sieve composition of the two, most preferably a molecularsieve catalyst composition of the two, the production of ethane andpropane is reduced by greater than 10%, preferably greater than 20%,more preferably greater than 30%, and most preferably in the range offrom about 30% to 50% compared to the molecular sieve alone or itscatalyst composition at the same conversion conditions.

The feedstock, in one embodiment, contains one or more diluent(s),typically used to reduce the concentration of the feedstock, and aregenerally non-reactive to the feedstock or molecular sieve catalystcomposition. Non-limiting examples of diluents include helium, argon,nitrogen, carbon monoxide, carbon dioxide, water, essentiallynon-reactive paraffins (especially alkanes such as methane, ethane, andpropane), essentially non-reactive aromatic compounds, and mixturesthereof. The most preferred diluents are water and nitrogen, with waterbeing particularly preferred.

The diluent, water, is used either in a liquid or a vapor form, or acombination thereof. The diluent is either added directly to a feedstockentering into a reactor or added directly into a reactor, or added witha molecular sieve catalyst composition.

The process for converting a feedstock, especially a feedstockcontaining one or more oxygenates, in the presence of a molecular sievecatalyst composition of the invention, is carried out in a reactionprocess in a reactor, where the process is a fixed bed process, afluidized bed process (includes a turbulent bed process), preferably acontinuous fluidized bed process, and most preferably a continuous highvelocity fluidized bed process.

The reaction processes can take place in a variety of catalytic reactorssuch as hybrid reactors that have a dense bed or fixed bed reactionzones and/or fast fluidized bed reaction zones coupled together,circulating fluidized bed reactors, riser reactors, and the like.Suitable conventional reactor types are described in for example U.S.Pat. No. 4,076,796, U.S. Pat. No. 6,287,522 (dual riser), andFluidization Engineering, D. Kunii and O. Levenspiel, Robert E. KriegerPublishing Company, New York, N.Y. 1977, which are all herein fullyincorporated by reference.

The preferred reactor type are riser reactors generally described inRiser Reactor, Fluidization and Fluid-Particle Systems, pages 48 to 59,F. A. Zenz and D. F. Othmo, Reinhold Publishing Corporation, New York,1960, and U.S. Pat. No. 6,166,282 (fast-fluidized bed reactor), and U.S.patent application Ser. No. 09/564,613 filed May 4, 2000 (multiple riserreactor), which are all herein fully incorporated by reference.

In the preferred embodiment, a fluidized bed process or high velocityfluidized bed process includes a reactor system, a regeneration systemand a recovery system.

The reactor system preferably is a fluid bed reactor system having afirst reaction zone within one or more riser reactor(s) and a secondreaction zone within at least one disengaging vessel, preferablycomprising one or more cyclones. In one embodiment, the one or moreriser reactor(s) and disengaging vessel is contained within a singlereactor vessel. Fresh feedstock, preferably containing one or moreoxygenates, optionally with one or more diluent(s), is fed to the one ormore riser reactor(s) in which a molecular sieve catalyst composition orcoked version thereof is introduced. In one embodiment, the molecularsieve catalyst composition or coked version thereof is contacted with aliquid or gas, or combination thereof, prior to being introduced to theriser reactor(s), preferably the liquid is water or methanol, and thegas is an inert gas such as nitrogen.

In an embodiment, the amount of fresh feedstock fed separately orjointly with a vapor feedstock, to a reactor system is in the range offrom 0.1 weight percent to about 85 weight percent, preferably fromabout 1 weight percent to about 75 weight percent, more preferably fromabout 5 weight percent to about 65 weight percent based on the totalweight of the feedstock including any diluent contained therein. Theliquid and vapor feedstocks are preferably the same composition, orcontain varying proportions of the same or different feedstock with thesame or different diluent.

The feedstock entering the reactor system is preferably converted,partially or fully, in the first reactor zone into a gaseous effluentthat enters the disengaging vessel along with a coked molecular sievecatalyst composition. In the preferred embodiment, cyclone(s) within thedisengaging vessel are designed to separate the molecular sieve catalystcomposition, preferably a coked molecular sieve catalyst composition,from the gaseous effluent containing one or more olefin(s) within thedisengaging zone. Cyclones are preferred, however, gravity effectswithin the disengaging vessel will also separate the catalystcompositions from the gaseous effluent. Other methods for separating thecatalyst compositions from the gaseous effluent include the use ofplates, caps, elbows, and the like.

In one embodiment of the disengaging system, the disengaging systemincludes a disengaging vessel, typically a lower portion of thedisengaging vessel is a stripping zone. In the stripping zone the cokedmolecular sieve catalyst composition is contacted with a gas, preferablyone or a combination of steam, methane, carbon dioxide, carbon monoxide,hydrogen, or an inert gas such as argon, preferably steam, to recoveradsorbed hydrocarbons from the coked molecular sieve catalystcomposition that is then introduced to the regeneration system.

The conversion temperature employed in the conversion process,specifically within the reactor system, is in the range of from about200° C. to about 1000° C., preferably from about 250° C. to about 800°C., more preferably from about 250° C. to about 750° C., yet morepreferably from about 300° C. to about 650° C., yet even more preferablyfrom about 350° C. to about 600° C. most preferably from about 350° C.to about 550° C.

The conversion pressure employed in the conversion process, specificallywithin the reactor system, varies over a wide range including autogenouspressure. The conversion pressure is based on the partial pressure ofthe feedstock exclusive of any diluent therein. Typically the conversionpressure employed in the process is in the range of from about 0.1 kPaato about 5 MPaa, preferably from about 5 kPaa to about 1 MPaa, and mostpreferably from about 20 kPaa to about 500 kPaa.

The weight hourly space velocity (WHSV), particularly in a process forconverting a feedstock containing one or more oxygenates in the presenceof a molecular sieve catalyst composition within a reaction zone, isdefined as the total weight of the feedstock excluding any diluents tothe reaction zone per hour per weight of molecular sieve in themolecular sieve catalyst composition in the reaction zone. The WHSV ismaintained at a level sufficient to keep the catalyst composition in afluidized state within a reactor.

Typically, the WHSV ranges from about 1 hr⁻¹ to about 5000 hr⁻¹,preferably from about 2 hr⁻¹ to about 3000 hr⁻¹, more preferably fromabout 5 hr⁻¹ to about 1500 hr⁻¹, and most preferably from about 10 hr⁻¹to about 1000 hr⁻¹. In one preferred embodiment, the WHSV is greaterthan 20 hr⁻¹, preferably the WHSV for conversion of a feedstockcontaining methanol and dimethyl ether is in the range of from about 20hr⁻¹ to about 300 hr⁻¹.

The superficial gas velocity (SGV) of the feedstock including diluentand reaction products within the reactor system is preferably sufficientto fluidize the molecular sieve catalyst composition within a reactionzone in the reactor. The SGV in the process, particularly within thereactor system, more particularly within the riser reactor(s), is atleast 0.1 meter per second (m/sec), preferably greater than 0.5 m/sec,more preferably greater than 1 m/sec, even more preferably greater than2 m/sec, yet even more preferably greater than 3 m/sec, and mostpreferably greater than 4 m/sec. See for example U.S. patent applicationSer. No. 09/708,753 filed Nov. 8, 2000, which is herein incorporated byreference.

The coked molecular sieve catalyst composition is withdrawn from thedisengaging vessel and introduced to the regeneration system. Theregeneration system comprises a regenerator where the coked catalystcomposition is contacted with a regeneration medium, preferably a gascontaining oxygen, under general regeneration conditions of temperature,pressure and residence time.

Non-limiting examples of the regeneration medium include one or more ofoxygen, O₃, SO₃, N₂O, NO, NO₂, N₂O₅, air, air diluted with nitrogen orcarbon dioxide, oxygen and water (U.S. Pat. No. 6,245,703), carbonmonoxide and/or hydrogen. The regeneration conditions are those capableof burning coke from the coked catalyst composition, preferably to alevel less than 0.5 weight percent based on the total weight of thecoked molecular sieve catalyst composition entering the regenerationsystem. The coked molecular sieve catalyst composition withdrawn fromthe regenerator forms a regenerated molecular sieve catalystcomposition.

The regeneration temperature is in the range of from about 200° C. toabout 1500° C., preferably from about 300° C. to about 1000° C., morepreferably from about 450° C. to about 750° C., and most preferably fromabout 550° C. to 700° C. The regeneration pressure is in the range offrom about 15 psia (103 kPaa) to about 500 psia (3448 kPaa), preferablyfrom about 20 psia (138 kPaa) to about 250 psia (1724 kPaa), morepreferably from about 25 psia (172 kPaa) to about 150 psia (1034 kPaa),and most preferably from about 30 psia (207 kPaa) to about 60 psia (414kPaa).

The preferred residence time of the molecular sieve catalyst compositionin the regenerator is in the range of from about one minute to severalhours, most preferably about one minute to 100 minutes, and thepreferred volume of oxygen in the gas is in the range of from about 0.01mole percent to about 5 mole percent based on the total volume of thegas.

In an embodiment, a portion of the molecular sieve catalyst compositionfrom the regenerator is returned directly to the one or more riserreactor(s), or indirectly, by pre-contacting with the feedstock, orcontacting with fresh molecular sieve catalyst composition, orcontacting with a regenerated molecular sieve catalyst composition or acooled regenerated molecular sieve catalyst composition described below.

The burning of coke is an exothermic reaction, and in an embodiment, thetemperature within the regeneration system is controlled by varioustechniques in the art including feeding a cooled gas to the regeneratorvessel, operated either in a batch, continuous, or semi-continuous mode,or a combination thereof. A preferred technique involves withdrawing theregenerated molecular sieve catalyst composition from the regenerationsystem and passing the regenerated molecular sieve catalyst compositionthrough a catalyst cooler that forms a cooled regenerated molecularsieve catalyst composition. The catalyst cooler, in an embodiment, is aheat exchanger that is located either internal or external to theregeneration system. Other methods for operating a regeneration systemare in disclosed U.S. Pat. No. 6,290,916 (controlling moisture), whichis herein fully incorporated by reference.

The regenerated molecular sieve catalyst composition withdrawn from theregeneration system, preferably from the catalyst cooler, is combinedwith a fresh molecular sieve catalyst composition and/or re-circulatedmolecular sieve catalyst composition and/or feedstock and/or fresh gasor liquids, and returned to the riser reactor(s). In another embodiment,the regenerated molecular sieve catalyst composition withdrawn from theregeneration system is returned to the riser reactor(s) directly,preferably after passing through a catalyst cooler. In one embodiment, acarrier, such as an inert gas, feedstock vapor, steam or the like,semi-continuously or continuously, facilitates the introduction of theregenerated molecular sieve catalyst composition to the reactor system,preferably to the one or more riser reactor(s).

By controlling the flow of the regenerated molecular sieve catalystcomposition or cooled regenerated molecular sieve catalyst compositionfrom the regeneration system to the reactor system, the optimum level ofcoke on the molecular sieve catalyst composition entering the reactor ismaintained. There are many techniques for controlling the flow of amolecular sieve catalyst composition described in Michael Louge,Experimental Techniques, Circulating Fluidized Beds, Grace, Avidan andKnowlton, eds., Blackie, 1997 (336-337), which is herein incorporated byreference.

Coke levels on the molecular sieve catalyst composition is measured bywithdrawing from the conversion process the molecular sieve catalystcomposition at a point in the process and determining its carboncontent. Typical levels of coke on the molecular sieve catalystcomposition, after regeneration is in the range of from 0.01 weightpercent to about 15 weight percent, preferably from about 0.1 weightpercent to about 10 weight percent, more preferably from about 0.2weight percent to about 5 weight percent, and most preferably from about0.3 weight percent to about 2 weight percent based on the total weightof the molecular sieve and not the total weight of the molecular sievecatalyst composition.

The gaseous effluent is withdrawn from the disengaging system and ispassed through a recovery system. There are many well known recoverysystems, techniques and sequences that are useful in separatingolefin(s) and purifying olefin(s) from the gaseous effluent. Recoverysystems generally comprise one or more or a combination of a variousseparation, fractionation and/or distillation towers, columns,splitters, or trains, reaction systems such as ethylbenzene manufacture(U.S. Pat. No. 5,476,978) and other derivative processes such asaldehydes, ketones and ester manufacture (U.S. Pat. No. 5,675,041), andother associated equipment for example various condensers, heatexchangers, refrigeration systems or chill trains, compressors,knock-out drums or pots, pumps, and the like.

Non-limiting examples of these towers, columns, splitters or trains usedalone or in combination include one or more of a demethanizer,preferably a high temperature demethanizer, a dethanizer, adepropanizer, a wash tower often referred to as a caustic wash towerand/or quench tower, absorbers, adsorbers, membranes, ethylene (C2)splitter, propylene (C3) splitter, butene (C4) splitter, and the like.

Various recovery systems useful for recovering predominately olefin(s),preferably prime or light olefin(s) such as ethylene, propylene and/orbutene are described in U.S. Pat. No. 5,960,643 (secondary rich ethylenestream), U.S. Pat. Nos. 5,019,143, 5,452,581 and 5,082,481 (membraneseparations), U.S. Pat. No. 5,672,197 (pressure dependent adsorbents),U.S. Pat. No. 6,069,288 (hydrogen removal), U.S. Pat. No. 5,904,880(recovered methanol to hydrogen and carbon dioxide in one step), U.S.Pat. No. 5,927,063 (recovered methanol to gas turbine power plant), andU.S. Pat. No. 6,121,504 (direct product quench), U.S. Pat. No. 6,121,503(high purity olefins without superfractionation), and U.S. Pat. No.6,293,998 (pressure swing adsorption), which are all herein fullyincorporated by reference.

Generally accompanying most recovery systems is the production,generation or accumulation of additional products, by-products and/orcontaminants along with the preferred prime products. The preferredprime products, the light olefins, such as ethylene and propylene, aretypically purified for use in derivative manufacturing processes such aspolymerization processes. Therefore, in the most preferred embodiment ofthe recovery system, the recovery system also includes a purificationsystem. For example, the light olefin(s) produced particularly in a MTOprocess are passed through a purification system that removes low levelsof by-products or contaminants.

Non-limiting examples of contaminants and by-products include generallypolar compounds such as water, alcohols, carboxylic acids, ethers,carbon oxides, sulfur compounds such as hydrogen sulfide, carbonylsulfides and mercaptans, ammonia and other nitrogen compounds, arsine,phosphine and chlorides. Other contaminants or by-products includehydrogen and hydrocarbons such as acetylene, methyl acetylene,propadiene, butadiene and butyne.

Other recovery systems that include purification systems, for examplefor the purification of olefin(s), are described in Kirk-OthmerEncyclopedia of Chemical Technology, 4th Edition, Volume 9, John Wiley &Sons, 1996, pages 249-271 and 894-899, which is herein incorporated byreference. Purification systems are also described in for example, U.S.Pat. No. 6,271,428 (purification of a diolefin hydrocarbon stream), U.S.Pat. No. 6,293,999 (separating propylene from propane), and U.S. patentapplication Ser. No. 09/689,363 filed Oct. 20, 2000 (purge stream usinghydrating catalyst), which is herein incorporated by reference.

Typically, in converting one or more oxygenates to olefin(s) having 2 or3 carbon atoms, an amount of hydrocarbons, particularly olefin(s),especially olefin(s) having 4 or more carbon atoms, and otherby-products are formed or produced. Included in the recovery systems ofthe invention are reaction systems for converting the products containedwithin the effluent gas withdrawn from the reactor or converting thoseproducts produced as a result of the recovery system utilized.

The effluent gas removed from a conversion process, particularly a MTOprocess, typically has a minor amount of hydrocarbons having 4 or morecarbon atoms. The amount of hydrocarbons having 4 or more carbon atomsis typically in an amount less than 20 weight percent, preferably lessthan 10 weight percent, more preferably less than 5 weight percent, andmost preferably less than 2 weight percent, based on the total weight ofthe effluent gas withdrawn from a MTO process, excluding water. Inparticular with a conversion process of oxygenates into olefin(s)utilizing a molecular sieve catalyst composition the resulting effluentgas typically comprises a majority of ethylene and/or propylene and aminor amount of four carbon and higher carbon number products and otherby-products, excluding water.

Non-limiting examples of reaction systems include U.S. Pat. No.5,955,640 (converting a four carbon product into butene-1), U.S. Pat.No. 4,774,375 (isobutane and butene-2 oligomerized to an alkylategasoline), U.S. Pat. No. 6,049,017 (dimerization of n-butylene), U.S.Pat. Nos. 4,287,369 and 5,763,678 (carbonylation or hydroformulation ofhigher olefins with carbon dioxide and hydrogen making carbonylcompounds), U.S. Pat. No. 4,542,252 (multistage adiabatic process), U.S.Pat. No. 5,634,354 (olefin-hydrogen recovery), and Cosyns, J. et al.,Process for Upgrading C3, C4 and C5 Olefinic Streams, Pet. & Coal, Vol.37, No. 4 (1995) (dimerizing or oligomerizing propylene, butylene andpentylene), which are all herein fully incorporated by reference.

The preferred light olefin(s) produced by any one of the processesdescribed above, preferably conversion processes, are high purity primeolefin(s) products that contains a single carbon number olefin in anamount greater than 80 percent, preferably greater than 90 weightpercent, more preferably greater than 95 weight percent, and mostpreferably no less than about 99 weight percent, based on the totalweight of the olefin.

In one embodiment, high purity prime olefin(s) are produced in theprocess of the invention at rate of greater than 5 kg per day,preferably greater than 10 kg per day, more preferably greater than 20kg per day, and most preferably greater than 50 kg per day. In anotherembodiment, high purity ethylene and/or high purity propylene isproduced by the process of the invention at a rate greater than 4,500 kgper day, preferably greater than 100,000 kg per day, more preferablygreater than 500,000 kg per day, even more preferably greater than1,000,000 kg per day, yet even more preferably greater than 1,500,000 kgper day, still even more preferably greater than 2,000,000 kg per day,and most preferably greater than 2,500,000 kg per day.

In an embodiment, an integrated process is directed to producing lightolefin(s) from a hydrocarbon feedstock, preferably a hydrocarbon gasfeedstock, more preferably methane and/or ethane. The first step in theprocess is passing the gaseous feedstock, preferably in combination witha water stream, to a syngas production zone to produce a synthesis gas(syngas) stream. Syngas production is well known, and typical syngastemperatures are in the range of from about 700° C. to about 1200° C.and syngas pressures are in the range of from about 2 MPa to about 100MPa. Synthesis gas streams are produced from natural gas, petroleumliquids, and carbonaceous materials such as coal, recycled plastic,municipal waste or any other organic material, preferably synthesis gasstream is produced via steam reforming of natural gas.

Generally, a heterogeneous catalyst, typically a copper based catalyst,is contacted with a synthesis gas stream, typically carbon dioxide andcarbon monoxide and hydrogen to produce an alcohol, preferably methanol,often in combination with water. In one embodiment, the synthesis gasstream at a synthesis temperature in the range of from about 150° C. toabout 450° C. and at a synthesis pressure in the range of from about 5MPa to about 10 MPa is passed through a carbon oxide conversion zone toproduce an oxygenate containing stream.

This oxygenate containing stream, or crude methanol, typically containsthe alcohol product and various other components such as ethers,particularly dimethyl ether, ketones, aldehydes, dissolved gases such ashydrogen methane, carbon oxide and nitrogen, and fuel oil. The oxygenatecontaining stream, crude methanol, in the preferred embodiment is passedthrough a well known purification processes, distillation, separationand fractionation, resulting in a purified oxygenate containing stream,for example, commercial Grade A and AA methanol.

The oxygenate containing stream or purified oxygenate containing stream,optionally with one or more diluents, is contacted with one or moremolecular sieve catalyst composition described above in any one of theprocesses described above to produce a variety of prime products,particularly light olefin(s), ethylene and/or propylene. Non-limitingexamples of this integrated process is described in EP-B-0 933 345,which is herein fully incorporated by reference.

In another more fully integrated process, optionally with the integratedprocesses described above, olefin(s) produced are directed to, in oneembodiment, one or more polymerization processes for producing variouspolyolefins. (See for example U.S. patent application Ser. No.09/615,376 filed Jul. 13, 2000, which is herein fully incorporated byreference.)

Polymerization processes include solution, gas phase, slurry phase and ahigh pressure processes, or a combination thereof. Particularlypreferred is a gas phase or a slurry phase polymerization of one or moreolefin(s) at least one of which is ethylene or propylene.

These polymerization processes utilize a polymerization catalyst thatcan include any one or a combination of the molecular sieve catalystsdiscussed above, however, the preferred polymerization catalysts arethose Ziegler-Natta, Phillips-type, metallocene, metallocene-type andadvanced polymerization catalysts, and mixtures thereof.

In preferred embodiment, the integrated process comprises a polymerizingprocess of one or more olefin(s) in the presence of a polymerizationcatalyst system in a polymerization reactor to produce one or morepolymer products, wherein the one or more olefin(s) having been made byconverting an alcohol, particularly methanol, using a molecular sievecatalyst composition. The preferred polymerization process is a gasphase polymerization process and at least one of the olefins(s) iseither ethylene or propylene, and preferably the polymerization catalystsystem is a supported metallocene catalyst system. In this embodiment,the supported metallocene catalyst system comprises a support, ametallocene or metallocene-type compound and an activator, preferablythe activator is a non-coordinating anion or alumoxane, or combinationthereof, and most preferably the activator is alumoxane.

The polymers produced by the polymerization processes described aboveinclude linear low density polyethylene, elastomers, plastomers, highdensity polyethylene, low density polyethylene, polypropylene andpolypropylene copolymers. The propylene based polymers produced by thepolymerization processes include atactic polypropylene, isotacticpolypropylene, syndiotactic polypropylene, and propylene random, blockor impact copolymers.

EXAMPLES

In order to provide a better understanding of the present inventionincluding representative advantages thereof, the following examples areoffered.

LEI is defined as the ratio of the lifetime of the molecular sievecomposition, or the catalyst composition described below, to that of themolecular sieve in the absence of a metal oxide as discussed above. Forthe purpose of determining LEI, lifetime is defined as the cumulativeoxygenate converted, preferably into one or more olefin(s) per gram ofmolecular sieve, wherein the conversion rate drops to about 10%. If theconversion has not reached 10% by the end of the experiment, lifetime isestimated by linear extrapolation based on the rate of decrease inconversion over the last two data points in the experiment. For thepurposes of determining the LEI for the following examples in apreferred oxygenate conversion process, methanol is converted to one ormore olefin(s) at 475° C., 25 psig (172 kPag) and a methanol weighthourly space velocity of 100 h⁻¹.

In Table 1, “Prime Olefin” is the sum of the selectivity to ethylene andpropylene. The ratio “C₂ ^(═)/C₃ ^(═)” is the ratio of the ethylene topropylene selectivity weighted over the run. The “C₃ Purity” iscalculated by dividing the propylene selectivity by the sum of thepropylene and propane selectivity. In Table 2, the selectivity formethane, ethylene, ethane, propylene, propane, C₄'s and C₅+'s areaverage selectivity weighted over the run. Note that the C₅+'s consistonly of C₅'s, C₆'s and C₇'s. The terms “C₄'s, C₅+, etc.” refer to thenumber of carbons in the hydrocarbon. The selectivity values do not sumto 100% in the Tables because they have been corrected for coke as iswell known.

Example A

Preparation of a Molecular Sieve

There are numerous methods well known for making molecular sieves. Thefollowing is an example preparation of a molecular sieve, particularly asilicoaluminophosphate molecular sieve, more particularly a SAPO-34,used in the compositions in these Examples, and referenced as MSA.

The MSA, SAPO-34 molecular sieve, was crystallized in the presence oftetraethyl ammonium hydroxide (R1) and dipropyl amine (R2) as theorganic structure directing agents or templating agents. A mixture ofthe following mole ratio composition was prepared:0.2SiO₂/Al₂O₃/P₂O₅/0.9R1/1.5R2/50H₂O.An amount of Condea Pural SB was mixed with deionised water, to form aslurry. To this slurry was added an amount of phosphoric acid (85%).These additions were made with stirring to form a homogeneous mixture.To this homogeneous mixture Ludox AS40 (40% of SiO2) was added, followedby the addition of R1 with mixing to form a homogeneous mixture. To thishomogeneous mixture R2 was added. This homogeneous mixture was thencrystallized with agitation in a stainless steel autoclave by heating to170° C. for 40 hours. This provided a slurry of the crystallinemolecular sieve. The crystals were then separated from the mother liquorby filtration.Formulation of a Molecular Sieve

There are a variety of methods for making or formulating a molecularsieve, a matrix material and a binder into a molecular sieve catalystcomposition. The following is an example of making a molecular sievecatalyst composition. The crystalline molecular sieve prepared above wasthoroughly mixed with water to form a molecular sieve slurry (A1). Thisslurry (A1) was then added to another slurry (A2) of a binder (forexample, preferably aluminum chlorhydrol) and water, and was then againmixed thoroughly. As a final step in the formulation process, a matrixmaterial (A3) (for example, a clay material) was then added to themixture of A1 and A2, mixed well to form a homogeneous mixture (A4).This mixture (A4) was then fed to a drier, preferably a spray drier,under conditions sufficient to produce a formulated molecular sievecatalyst composition composed of particles having the desired size anddryness. Spray drying is well known, and is further discussed in thispatent specification. The molecular sieve catalyst composition producedis then calcined at an elevated temperature sufficient to further dryand harden the spray dried molecular sieve catalyst composition orformulated molecular sieve catalyst composition. The catalystcomposition is then packaged under a dry atmosphere for use, storage orshipment.

Example B

Conversion Process

All catalytic or conversion data presented was obtained using amicroflow reactor. The microflow reactor consists of a stainless steelreactor (¼ inch (0.64 cm) outer diameter) located in a furnace to whichvaporized methanol is fed. The reactor is maintained at a temperature of475° C. and a pressure of 25 psig (172.4 kPag). The flow rate of themethanol is such that the flow rate of methanol on weight basis per gramof molecular sieve, also known as the weight hourly space velocity(WHSV) was 100 h⁻¹. Product gases exiting the reactor are collected andanalyzed using gas chromatography. The molecular sieve alone or themolecular sieve composition load was 50 mg and the reactor bed wasdiluted with quartz to minimize hot spots in the reactor. In particular,for the catalyst composition of the invention, the molecular sieve andactive Group 3 metal oxide or oxide of the Lanthanide or Actinide serieselements, a physical mixture of the MSA molecular sieve of Example A andthe active metal oxide was used. The total catalyst composition loadremained 50 mg, 40 mg of the molecular sieve catalyst composition and 10mg of the Group 3 metal oxide, and the methanol flow rate was adjustedas the amount of molecular sieve in the reactor bed was changed by theaddition of the active metal oxide such that the methanol WHSV was 100h⁻¹ based on the amount of molecular sieve in the reactor bed.

Examples 1 through 7 describe the synthesis of the active metal oxidefor use with the molecular sieve catalyst composition, in particularlywhere the molecular sieve is a SAPO-34. Examples 8 through 15 describethe performance of the molecular sieve catalyst composition and theactive metal oxide, with a comparison of the same molecular sievecatalyst composition without an active metal oxide.

Example 1

A sample of La(NO₃)₃.xH₂O (Aldrich Chemical Company) was calcined in airat 700° C. for 3 hours to produce lanthanum oxide.

Example 2

Fifty grams of La(NO₃)₃.xH₂O (Aldrich Chemical Company) were dissolvedwith stirring in 500 ml of distilled water. The pH was adjusted to 9 bythe addition of concentrated ammonium hydroxide. This slurry was thenput in polypropylene bottles and placed in a steambox (100° C.) for 72hours. The product formed was recovered by filtration, washed withexcess water, and dried overnight at 85° C. A portion of this catalystwas calcined to 600° C. in flowing air for 3 hours to produce lanthanumoxide (La₂O₃).

Example 3

Fifty grams of Y(NO₃)₃.6H₂O were dissolved with stirring in 500 ml ofdistilled water. The pH was adjusted to 9 by the addition ofconcentrated ammonium hydroxide. This slurry was then put inpolypropylene bottles and placed in a steambox (100° C.) for 72 hours.The product formed was recovered by filtration, washed with excesswater, and dried overnight at 85° C. A portion of this catalyst wascalcined to 600° C. in flowing air for 3 hours to produce yttrium oxide(Y₂O₃).

Example 4

A sample of Sc(NO₃)₃.xH₂O (Aldrich Chemical Company) was calcined in airat 700° C. for 3 hours to produce scandium oxide (Sc₂O₃).

Example 5

Fifty grams of Ce(NO₃)₃.6H₂O were dissolved with stirring in 500 ml ofdistilled water. The pH was adjusted to 9 by the addition ofconcentrated ammonium hydroxide. This slurry was then put inpolypropylene bottles and placed in a steambox (100° C.) for 72 hours.The product formed was recovered by filtration, washed with excesswater, and dried overnight at 85° C. A portion of this catalyst wascalcined to 600° C. in flowing air for 3 hours to produce cerium oxide(Ce₂O₃).

Example 6

Fifty grams of Pr(NO₃)₃.6H₂O were dissolved with stirring in 500 ml ofdistilled water. The pH was adjusted to 8 by the addition ofconcentrated ammonium hydroxide. This slurry was then put inpolypropylene bottles and placed in a steambox (100° C.) for 72 hours.The product formed was recovered by filtration, washed with excesswater, and dried overnight at 85° C. A portion of this catalyst wascalcined to 600° C. in flowing air for 3 hours to produce praseodymiumoxide (Pr₂O₃).

Example 7

Fifty grams of Nd(NO₃)₃.6H₂O were dissolved with stirring in 500 ml ofdistilled water. The pH was adjusted to 9 by the addition ofconcentrated ammonium hydroxide. This slurry was then put inpolypropylene bottles and placed in a steambox (100° C.) for 72 hours.The product formed was recovered by filtration, washed with excesswater, and dried overnight at 85° C. A portion of this catalyst wascalcined to 600° C. in flowing air for 3 hours to produce neodymiumoxide (Nd₂O₃).

Comparative Example 8

In this Comparative Example 8 (CEx. 8) the molecular sieve catalystcomposition produced in Example A was tested in accordance with theprocess of Example B using 50 mg of the molecular sieve catalystcomposition without an active metal oxide. The results of the run arepresented in Table 1 and Table 2.

Example 9

In this Example 9, the molecular sieve catalyst composition produced inExample A was tested in accordance with the process of Example B using40 mg of the molecular sieve catalyst composition with 10 mg of La₂O₃produced via nitrate decomposition in Example 1. The components werewell mixed and then diluted with sand to form the reactor bed. Theresults of this Example 9 are shown in Table 1 and Table 2 illustratingthat the addition of La₂O₃, an active Group 3 metal oxide, increasedlifetime by 149%. Selectivity to ethane decreased by 36% and selectivityto propane decreased by 32%, suggesting a significant reduction inhydrogen transfer reactions.

Example 10

In this Example 10, the molecular sieve catalyst composition produced inExample A was tested in accordance with the process of Example B using40 mg of the molecular sieve catalyst composition with 10 mg of La₂O₃produced via precipitation in Example 2. The components were well mixedand then diluted with sand to form the reactor bed. The results of thisExample 10 are shown in Table 1 and Table 2 illustrating that theaddition of La₂O₃ produced via precipitation, an active Group 3 metaloxide, increased lifetime by 340%. Selectivity to ethane decreased by55% and selectivity to propane decreased by 44%, suggesting asignificant reduction in hydrogen transfer reactions.

Example 11

In this Example 11, the molecular sieve catalyst composition produced inExample A was tested in accordance with the process of Example B using40 mg of the molecular sieve catalyst composition with 10 mg of Y₂O₃produced in Example 3. The components were well mixed and then dilutedwith sand to form the reactor bed. The results of this Example 11 areshown in Table 1 and Table 2 illustrating that the addition of Y₂O₃, anactive Group 3 metal oxide, increased lifetime by 1090%. Selectivity toethane decreased by 45% and selectivity to propane decreased by 28%,suggesting a significant reduction in hydrogen transfer reactions.

Example 12

In this Example 12, the molecular sieve catalyst composition produced inExample A was tested in accordance with the process of Example B using40 mg of the molecular sieve catalyst composition with 10 mg of Sc₂O₃produced in Example 4. The components were well mixed and then dilutedwith sand to form the reactor bed. The results of this Example 12 areshown in Table 1 and Table 2 illustrating that the addition of Sc₂O₃, anactive Group 3 metal oxide, increased lifetime by 167%. Selectivity toethane decreased by 27% and selectivity to propane decreased by 21%,suggesting a significant reduction in hydrogen transfer reactions.

Example 13

In this Example 13, the molecular sieve catalyst composition produced inExample A was tested in accordance with the process of Example B using40 mg of the molecular sieve catalyst composition with 10 mg of Ce₂O₃produced in Example 5. The components were well mixed and then dilutedwith sand to form the reactor bed. The results of this Example 13 areshown in Table 1 and Table 2 illustrating that the addition of Ce₂O₃, anactive Lanthanide metal oxide, increased lifetime by 630%. Selectivityto ethane decreased by 50% and selectivity to propane decreased by 34%,suggesting a significant reduction in hydrogen transfer reactions.

Example 14

In this Example 14, the molecular sieve catalyst composition produced inExample A was tested in accordance with the process of Example B using40 mg of the molecular sieve catalyst composition with 10 mg of Pr₂O₃produced in Example 6. The components were well mixed and then dilutedwith sand to form the reactor bed. The results of this Example 14 areshown in Table 1 and Table 2 illustrating that the addition of Pr₂O₃, anactive Lanthanide metal oxide, increased lifetime by 640%. Selectivityto ethane decreased by 51% and selectivity to propane decreased by 38%,suggesting a significant reduction in hydrogen transfer reactions.

Example 15

In this Example 15, the molecular sieve catalyst composition produced inExample A was tested in accordance with the process of Example B using40 mg of the molecular sieve catalyst composition with 10 mg of Nd₂O₃produced in Example 7. The components were well mixed and then dilutedwith sand to form the reactor bed. The results of this Example 15 areshown in Table 1 and Table 2 illustrating that the addition of Nd₂O₃, anactive Lanthanide metal oxide, increased lifetime by 340%. Selectivityto ethane decreased by 49% and selectivity to propane decreased by 34%,suggesting a significant reduction in hydrogen transfer reactions.

TABLE 1 Lifetime Prime C₃ Exam- Reactor Bed Extension Olefin C₂ ⁼/Purity ple Composition Index (LEI) (%) C₃ ⁼ (%) CEx. 8 100% MSA 1.072.99 0.90 94.1  9 80% MSA/20% La₂O₃ 2.5 73.84 0.81 96.1 10 80% MSA/20%La₂O₃ 4.4 73.78 0.74 96.9 11 80% MSA/20% Y₂O₃ 11.9 73.68 0.76 96.0 1280% MSA/20% Sc₂O₃ 2.7 73.74 0.81 95.5 13 80% MSA/20% Ce₂O₃ 7.3 70.510.69 96.3 14 80% MSA/20% Pr₂O₃ 7.4 72.37 0.72 96.6 15 80% MSA/20% Nd₂O₃4.4 72.57 0.71 96.3

TABLE 2 Exam- Reactor Bed ple Composition CH₄ C₂ ⁼ C₂ ^(O) C₃ ⁼ C₃ ^(O)C₄'s C₅+ CEx. 8 100% MSA 2.04 34.50 0.78 38.49 2.43 14.01 3.82  9 80%MSA/ 1.61 33.05 0.50 40.79 1.65 14.96 4.51 20% La₂O₃ 10 80% MSA/ 1.3831.43 0.35 42.35 1.37 15.03 5.51 20% La₂O₃ 11 80% MSA/ 1.39 31.85 0.4341.83 1.74 14.43 5.61 20% Y₂O₃ 12 80% MSA/ 1.67 33.08 0.57 40.66 1.9314.49 4.45 20% Sc₂O₃ 13 80% MSA/ 2.05 28.89 0.39 41.62 1.61 15.29 6.8320% Ce₂O₃ 14 80% MSA/ 1.59 30.18 0.38 42.19 1.51 15.22 6.06 20% Pr₂O₃ 1580% MSA/ 1.64 30.2 0.40 42.37 1.61 15.13 5.68 20% Nd₂O₃

While the present invention has been described and illustrated byreference to particular embodiments, those of ordinary skill in the artwill appreciate that the invention lends itself to variations notnecessarily illustrated herein. For example, it is contemplated that aplug flow, fixed bed or fluidized bed process are used in combination,particularly in different reaction zones within a single or multiplereactor system. It is also contemplated the molecular sieve compositionsdescribed herein are useful as absorbents, adsorbents, gas separators,detergents, water purifiers, and for other various uses such asagriculture and horticulture. It is within the scope of this inventionto add one or more active Group 3 metal oxide(s) to the synthesismixture for making a molecular sieve as described above. Also, it iscontemplated that one or more molecular sieves are used in the catalystcomposition. For this reason, then, reference should be made solely tothe appended claims for purposes of determining the true scope of thepresent invention.

1. A process for converting a feedstock comprising contracting one ormore oxygenate(s) with one or more olefin(s) in the presence of amolecular sieve catalyst composition comprising a molecular sieve, abinder, a matrix material and a Group 3 metal oxide and/or an oxide ofthe Lanthanide or Actinide series elements.
 2. The process of claim 1wherein the molecular sieve is synthesized from the combination from atleast two of the group consisting of a silicon source, a phosphoroussource and an aluminum source, and optionally in the presence of atemplating agent.
 3. The process of claim 1 wherein the metal of theGroup 3 metal oxide or the oxide of the Lanthanide or Actinide serieselements is selected from one of the group consisting of scandium,yttrium, lanthanum, cerium, praseodymium and neodymium.
 4. The processof claim 1 wherein the metal of Group 3 metal oxide is yttrium.
 5. Theprocess of claim 1 wherein the Group 3 metal oxide or the oxide of theLanthanide or Actinide series element is selected from one of the groupconsisting of lanthanum oxide, yttrium oxide, scandium oxide, ceriumoxide, praseodymium oxide and neodymium oxide, or mixtures thereof. 6.The process of claim 1 wherein the molecular sieve catalyst compositionhas a Lifetime Enhancement Index (LEI) greater than 1.1.
 7. The processof claim 1 wherein the molecular sieve is a silicoaluminophosphatemolecular sieve and/or an aluminophosphate molecular sieve.
 8. Theprocess of claim 1 wherein the oxygenate(s) comprises methanol and/ordimethylether.
 9. The process of claim 1 wherein the olefins(s) includeethylene and propylene, the molecular sieve is a silicoaluminophosphatemolecular sieve, the oxygenate(s) comprises methanol, the Group 3 metaloxide is yttrium oxide, the binder is an alumina sol, and the matrixmaterial is a clay.
 10. A process for producing one or more olefin(s),the process comprising the steps of: (a) introducing a feedstockcomprising at least one oxygenate to a reactor system in the presence ofa molecular sieve catalyst composition comprising a molecular sieve, abinder, a matrix material, and a Group 3 metal oxide and/or an oxide ofthe Lanthanide or Actinide series elements; (b) withdrawing from thereactor system an effluent stream; and (c) passing the effluent streamthrough a recovery system; and (d) recovering at least the one or moreolefin(s).
 11. The process of claim 10 wherein the binder is an aluminasol.
 12. The process of claim 10 wherein the matrix material is a clay.13. The process of claim 10 wherein the molecular sieve is asilicoaluminophosphate molecular sieve and/or an aluminophosphatemolecular sieve.
 14. The process of claim 10 wherein the Group 3 metaloxide is a lanthanum oxide or a yttrium oxide or a mixture thereof. 15.The process of claim 10 wherein the feedstock comprises methanol and/ordimethylether.
 16. The process of claim 10 wherein the LEI of themolecular sieve catalyst composition is greater than that for the samemolecular sieve catalyst composition without the Group 3 metal oxide orthe oxide of the Lanthanide or Actinide series elements.
 17. The processof claim 10 wherein the Group 3 metal oxide is yttrium oxide.
 18. Theprocess of claim 10 wherein the molecular sieve catalyst composition hasa LEI greater than 1.5.
 19. The process of claim 10 wherein theolefin(s) include ethylene and propylene.
 20. A process for converting afeedstock comprising contracting one or more oxygenate(s) with one ormore olefin(s) in the presence of a molecular sieve catalyst compositionprepared by a method for making the molecular sieve catalystcomposition, the method comprising the steps of: (i) forming an activeGroup 3 metal oxide or an active oxide of a Lanthanide or Actinideseries element, (ii) synthesizing a molecular sieve from the combinationof at least two of the group consisting of a silicon source, aphosphorous source and an aluminum source, optionally in the presence ofa templating agent, and (iii) introducing a binder, optionally with amatrix material.
 21. A process for converting a feedstock comprisingcontracting one or more oxygenate(s) with one or more olefin(s) in thepresence of a molecular sieve composition prepared by a method of makingthe molecular sieve composition, the method comprising the steps of: (i)synthesizing a molecular sieve by the method comprising the steps of:(a) forming a first reaction mixture of at least one templating agentand at least two of the group consisting of a silicon source, aphosphorous source and an aluminum source; and (b) removing themolecular sieve from the first reaction mixture; (ii) forming an activemetal oxide by the method comprising the steps of: (a) forming a secondreaction mixture comprising a Group 3 or Lanthanide or Actinide serieselement metal oxide precursor and a precipitating agent, (b) removingthe active metal oxide from the second reaction mixture; and (iii)combining the molecular sieve and the active metal oxide.
 22. Anintegrated process for making one or more olefin(s), the integratedprocess comprising the steps of: (a) passing a hydrocarbon feedstock toa syngas production zone to produce a synthesis gas stream; (b)contacting the synthesis gas stream with a catalyst to form anoxygenated feedstock; and (c) converting thin oxygenated feedstock intothe one or more olefin(s) in the presence of a molecular sieve catalystcomposition comprising a molecular sieve and an active metal oxide, themetal selected from Group 3 or Lanthanide or Actinide series elements ofthe Periodic Table of Elements.
 23. The integrated process of claim 22wherein the oxygenated feedstock comprises methanol and the olefin(s)include ethylene and propylene.
 24. The integrated process of claim 22wherein the molecular sieve is a silicoaluminophosphate molecular sieve.